Brake



July 9, 1940. l R. A GOEPFRlCH 2,207,172

BRAKE Filed Jan. 7, 1937 L l v( az fa? Will/[LVII] O v k O "lll/111111111 INVENToR RuooLP/f ZGoePF/P/CH BY ATTOR N EY Patented July 9*, 1940 l UNITED STAT-Es PATENT OFFICE BRAKE,v

Rudolph A. dnepfricn, south nena, rnd., assignmto Bendixlfroducts Qorporation, South Bend, Ind., a. corporation of Indiana Appumionjsanuuy 7, 19e/z, serial No'. 119,382

s claims. (criss-79.5)

the lining of the shoeiwhich does most of the` work in forward braking wears dow'n much faster l thanthe lining of the other shoe.

verging wedgesurfaces sloping at different angles. A. l Thus by crowding a thrust |member between these surfaces the shoes are wedged apart at the y desired diierent rates.

Another feature of the invention relates to arranging an adjustment of this type so that' in 0 forward braking the brake acts as a servo brake,

the one shoe operating the other, while in reverse braking the shoes are anchored on theva'djustment.

The above and other objects and features of the invention, including various novel combinations of parts and desirable particular arrangements, will be apparent from the following description of the' illustrative embodiments shown in the accompanying drawing, in which: I 80 Figure 1 is a partial section through a brake embodying the invention, in a plane just inside the head of the backing plate, and showing the connected ends of the shoes in side elevation;

Figure 2 is a partial section therethrough on the line 2-2 of Figure 1; Figure 3 is ar partial section corresponding to Figure 1, but showing a diil'erent embodiment; and

Figure 4 is a partial section therethrough .on o the line -t of Figure 3.

brake of the type fully illustrated and described in Patent No. 2,045,010, granted Bendix Aviation orporation June 23', 1936, on an application 4,5 led by me December 1, 1932. Where the parts illustrated herein are the same as, -or analogous to, those shown in the patent the reference characters of thepatent are used herein.

'The brake lillustrated includes a rotatable drum 24, at the open side of which is a support such as a backing plate 28, and, within which are ar'- ranged brake shoes 80 and 82. 'Ihe brake is provided with suitable anchorage and applying means, positioning stops, return springs, and steady rests, as described in said Patent No.

- adiatce able stamping |20. The invention is illustrated as embodied in a =ch rageior the brake.

2,045,010.l A spring 92'may begtensioned between v thel shoes to holdA them against the plungers de-l scribed below.

The webs of the shoes ao and s2 are held by spring 9 2 seated in -slots formed crosswise of 6 heads on the ends of alined plungers 96 arranged end to endfor sliding movement in cylindrical passages in. a; support or bracket96v secured to the backing plate by suitable fastening devices. 'Ihe nt inner ends of the plungers 94v are bev- 10 eled to form converging wedge surfaces, one of these surfaces slopingat a different angle than the other so that one shoe is adjusted faster than the other as explained above. p

-Between the plungers 94 is a wedge thrust 15 member N88 having correspondingly-sloping wedge faces, and which is formed as an integral part of a generally-cubical block |08 movably arranged v y in the bracket 96. The rectangular base of block 1081s formed with a groove or keyway- |09 ex- 20 tending circumferentially of the brake and parl alleling the plungers 94 and embracing a corresponding rib on a plate H0. This plate isv pro- .vided with radial grooves Ill on its opposite face for yielding interlocking4 engagement with cor- 25 -responding ridges on the face of the head ||2 of when the brake is applied. When the brake is 35 released the plunger ||6 returns the block |08 to acentered'position;

The -opening in the bracket 96 through which the parts are assembled is shown closed by a suit- The embodiment of Figures 3 and 4 differs from that described above principally in that block 208, carrying the wedge 98is large enough so that one side .(at the right in Figure A4) normally seats against the side wall 291 of the opening in the `i5 bracket 96. which contains the, vadjusting parts. 'I'hus the block 208 is free to shift to the left in Flgure4, but not to the right.

Therefore, in forward braking the shoe -applies the shoe 82 through the wedge 98, with a 50 servo-action, the anchorage being at the opposite side of the'brake as described in Patent No. 2,045,010, whereas in reverse braking (since block 208 cannot shift) the bracket 96 4forms the an- 4 Preferably there is a spring |22 tensioned between shoe 82 and the backing plate, to hold the block 208 yieldingly in the anchored position oi' Figure 4. While two illustrative embodiments have been described in detail, it is not my intention to limit the scope of the invention to those particular embodiments, or otherwise than by the terms of the appended claims. v

l. A brake having shoes provided with a shiftable connection including a pair of plungers arranged end to end and engaging the shoes respectively, means for guiding said piungers, and a member between the adjacent ends of said plungers, said member 'and said ends having surfaces in wedging engagement and with the surface on one plunger at a diilerent angle from that on the other, so that crowding saidl member 20 between said surfaces wedges the shoes apart with L one moved further than the other, in combination with means carried by the guiding means and operable to crowd said memherbetween'said plungers. said crowding means having a yielding 25 centering device acting on said member.

2. A brake having shoes provided'with'a shiftable connection including a pair of plungers arranged end to end and engaging the shoes respectively, means for guiding said plungers, and a member vbetween the adjacent ends of "said plungers, said member and said ends having surfaces in wedging engagement and with the sur;7 face on one plunger at a diierent angle from that on the other, so that crowding said member between said surfaces wedges the shoes apart with one moved further than the other, in combination with means carried bythe guiding means and operable to crowd said member between said plungers, and-a yielding centering device acting on said member. 1

a. a brake having shoes provided with a smftable connection including a pair of plungers arranged end to end and engaging theshoes reyon the other, so that crowding said member between said surfaces wedges the shoes apart with one moved further. than the other, in combination with a member carried by and having a stem threaded into the guiding means and having a head engaging said member and operable to crowd said member between said plungers, said stem having a socket formed therein and provided with a centering plunger acting on said member.

RUDOLPH A. GOEPFRICH. 

